Copper-zinc alloy

ABSTRACT

A copper-zinc alloy includes 56-65% by weight copper (Cu), 0.2-2.0%, by weight, of Tin (Sn) for improving tensile strength of Copper (Cu) and for strengthening the corrosion resistance of Zinc (Zn), 0.1-1.0%, by weight, of Aluminum (Al) for improving the yielding and tensile strength and corrosion resistance of the alloy, 0.01-0.6%, by weight, of Nickel (Ni) for strengthening the yielding and the tensile strength and the resistance and the heat conductivity of the alloy, lower than 0.5%, by weight, of Ferrite (Fe), with the balance being Zinc (Zn) and inevitable impurities.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related to the lead free Copper-Zinc alloy, which particularly focuses on reducing amounts of Copper material for decreasing the cost of the lead free Copper-Zinc alloy and to prevent the Copper-Zinc alloy from polluting our environment.

2. Description of the Prior Art

Typical Copper alloys comprise number of materials, such as Iron (Fe), Aluminum (Al), Tin (Sn), Nickel (Ni), and unavoidable impurities for improving the corrosion resistance, the wear resistance, or the bending strength or the like.

For example, U.S. Pat. No. 4,990,309 to Miyafuji et al. discloses one of the typical high strength Copper-Nickel-Tin-Zinc-Aluminum alloys containing Nickel (Ni), Tin (Sn), Aluminum (Al), Manganese (Mg), Zinc (Zn), Chromium (Cr), the balance of Copper and inevitable impurities.

The typical high strength Copper-Nickel-Tin-Zinc-Aluminum alloy contains a large amount of the Copper up to 80% in terms of weight. However, the Copper is an expensive material that may greatly increase the cost of the alloy and that may greatly lower the competition of the alloy.

U.S. Pat. No. 5,658,401 to Gaag et al. discloses another typical copper-zinc alloy for semi-finished products and articles which are higly loaded and subjected to extreme wear especially synchronizing rings.

However, the typical copper-zinc alloy includes the Lead (Pb) engaged therein which is not good for the user and which may pollute our environment.

U.S. Pat. No. 7,128,871 to Davitz discloses a further typical silver-colored, tarnish-resistant, corrosion-resistant alloy with low percentages of copper and zinc for jewelry items, tableware items, dental items or other items that should resist tarnishing or corrosion and which require a non-brittle alloy.

However, the typical silver-colored alloy includes a large amount of the silver up to about 92-95% in terms of weight which is an expensive material that may greatly increase the cost of the alloy and that may greatly weaken the competition of the alloy.

The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the onventional copper-zinc alloys.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a Copper-Zinc alloy including a reducing amount of copper material for decreasing the cost of the copper-zinc alloy and including no lead engaged therein for preventing the copper-zinc alloy from polluting our environment.

In accordance with one aspect of the invention, there is provided a Copper-Zinc alloy comprising 56-65%, by weight, of Copper (Cu), 0.2-2.0%, by weight, of Tin (Sn) for improving the tensile strength and the elongation property of Copper (Cu) and for strengthening the corrosion resistance of Zinc (Zn), 0.1-1.0%, by weight, of Aluminum (Al) for ameliorating the yielding strength and the tensile strength and the elongation property and the corrosion resistance of the alloy, 0.01-0.6%, by weight, of Nickel (Ni) for improving the yielding strength and the tensile strength and the resistance and the heat conductivity of the alloy, lower than 0.5%, by weight, of Ferrite (Fe), with the balance being Zinc (Zn) and inevitable impurities.

Further objectives and advantages of the present invention will become apparent from a careful reading of the detailed description provided herein below, with appropriate reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A copper-zinc alloy in accordance with the present invention primarily comprises a Copper (Cu) including about 56-65% in terms of weight that is relatively lower than that contained in the typical Copper-Zinc lead free alloys to lower the cost of the Copper-Zinc alloy. Tin (Sn), including 0.2-2.0% in terms of weight, may improve the tensile strength and the elongation property of Copper (Cu) and may also strengthen the corrosion resistance of Zinc (Zn). However, when the amounts of Tin (Sn) increases, the relatively fragile or brittle material: CuZnSn may be generated and may influence the deformation of the alloy, but may improve the cutting characteristic to the alloy.

For example, when the amounts of Tin (Sn) are lower than 0.3%, the cutting effect of the alloy may not be improved, and when the amounts of Tin (Sn) are more than 0.8%, the cutting effect and the tensile strength and the elongation property of the alloy may be improved or strengthened and the corrosion resistance of Zinc (Zn) may be gradually improved. When the amounts of Tin (Sn) is more than 2.0%, the corrosion speed of Zinc (Zn) is about 0.010 mm/Hr, the more Zinc (Zn) the better the cutting effect of the alloy and the better the corrosion resistance of zinc (Zn). However, when too much Zinc (Zn) is contained in the alloy, the stretchability of the alloy will be weakened, such that the best amounts of Tin (Sn) are about 0.2-2.0% in terms of weight.

The alloy further includes Aluminum (Al) having amounts of about 0.1-1.0% in terms of weight, which may improve the yielding strength and the tensile strength and the elongation property and the corrosion resistance of the Copper alloy, but may slightly weaken the stretchability of the Copper alloy, and too much percentage of Aluminum (Al) may decrease the stretchability of the alloy such that the copper alloy may be suitably machined or worked or molded or cast when the amount of Aluminum (Al) is about 0.1-1.0% in terms of weight, in addition, the specific weight of Aluminum (Al) is relatively lower such that the specific weight of the alloy may also be relatively decreased. Both Aluminum (Al) and Tin (Sn) may improve the cutting effect of the alloy.

The alloy may further comprise Iron (Fe), which could be well mixed the particle of the alloy. However, Iron (Fe) which contain too much inside alloy may weaken the property of corrosion resistance. Therefore, alloy could not contain too much percentage of Iron (Fe) therein. And the amount of Iron (Fe) is preferably no more than 0.5%, in terms of weight. The alloy may further comprise unavoidable impurities therein.

The alloy may further comprise Nickel (Ni) which may minimize the particle of the alloy and may increase the yielding strength and the tensile strength and the resistance and the heat conductivity of the alloy, and may improve the heating and the machining or forging of the alloy, and may strengthen the corrosion resistance of the alloy, such that the amount of Nickel (Ni) is preferably about between 0.01-0.6% in terms of weight.

The balance of the alloy is Zinc (Zn) which may remarkably improve the heat resistant peel ability of tin or alloy, and may improve the yielding strength and the tensile strength of the alloy. When the amount of Zinc (Zn) is more than 20%, the corrosion of the alloy may be occurred in the humidity environment or in sea water, particularly when the environment contains ammonia (NH₃). The cutting effect of the alloy may be suitably improved when the amounts of Zinc (Zn) is more than 33%, but too much Zinc (Zn) may decrease the molding of the alloy, such that the amounts of Zinc (Zn) may not exceed 45%.

Accordingly, the copper-zinc alloy in accordance with the present invention includes a decreased amount of copper material for decreasing the cost of the Copper-Zinc alloy and including no lead engaged therein for preventing the copper-zinc alloy from polluting our environment.

Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed. 

1. A copper-zinc alloy comprising: 56-65%, by weight, of Copper (Cu), 0.2-2.0%, by weight, of Tin (Sn), 0.1-1.0%, by weight, of Aluminum (Al), 0.01-0.6%, by weight, of Nickel (Ni), lower than 0.5%, by weight, of Ferrite (Fe), with the balance being zinc (Zn) and inevitable impurities. 